1. Field of the Invention
The invention is directed to a trash handling apparatus for a self-cleaning rotary screen.
2. Description of the Prior Art
In recent years it has become common practice to enclose the internal combustion engines of large self-propelled agricultural combines. Typically these enclosures are provided with self-cleaning rotary screens through which a cooling air stream is drawn. Heat exchangers are located behind the screen and include the radiator for cooling the engine, the oil cooler, and the condenser coils for the air conditioning. The screen is used to remove chaff, leaves and other large particulate matter from the cooling air stream so they do not block the various heat exchangers located behind the screen.
It is desirable that the screen be automatically and continuously self cleaning to facilitate air flow through the screen. One method of accomplishing this task is to rotate the screen through a stationary chamber which is used to vacuum the trash accumulated on the screen. This stationary chamber may be pneumatically coupled to the clean air stream downstream of the heat exchanger for reintroducing the trash collected off the screen into the air stream. In another design, the screen is held stationary and the vacuum chamber is rotated about the screen.
Sometimes, corn leaves plug the leading edge of the vacuum chamber. Corn leaves may also plug the chamber itself. These leaves become lodged in the elbow of the chamber. The long corn leaves do not break down, causing a bridging effect across the duct allowing additional leaves to build up behind it.